With each nanometer shrink or new micro-architecture there will always be performance gains. Each generation of new micro architecture has always boost performances compared to the previous generation clock-for-clock, more IPC (instruction per clock) or OPC (operation per clock) and bring along increase overclocking capabilities.
Don't be surprise if a 2.4Ghz Nehalme is as fast as the 3.0Ghz Core 2 Duo/Quad
